1. To be present in the real word; to be: Some people wonder if life really exists on other planets.
2. To live, especially under difficult conditions; to survive: After losing his wife and job, Sam existed or subsisted on very little and had to beg to stay alive.
3. To take place or occur in a certain place or situation: The problem of bicyclists riding on the streets in town still exists although some roads have been improved and have special bike lanes.